Astronomy and Astrophysics – Astrophysics – Solar and Stellar Astrophysics
Scientific paper
2012-04-03
Astronomy and Astrophysics
Astrophysics
Solar and Stellar Astrophysics
38 pages, 9 figures, submitted to the ApJ
Scientific paper
Modern theoretical models of astrophysical jets combine accretion, rotation, and magnetic fields to launch and collimate supersonic flows from a central source. Near the source, magnetic field strengths must be large enough to collimate the jet requiring that the Poynting flux exceeds the kinetic-energy flux. The extent to which the Poynting flux dominates kinetic energy flux at large distances from the engine distinguishes two classes of models. In magneto-centrifugal launch (MCL) models, magnetic fields dominate only at scales of order 100 engine radii or less, after which the jets become hydrodynamically dominated (HD). By contrast, in Poynting flux dominated (PFD) magnetic tower models, the field dominates even out to much larger scales. To compare the large distance propagation differences of these two paradigms, we perform 3-D ideal MHD AMR simulations of both HD and PFD jets formed via the same energy flux. We also compare how thermal energy losses and rotation of the jet base affects the stability in these jets. For the conditions described, we show that PFD and HD exhibit observationally distinguishable features: PFD jets are lighter, slower, and less stable than HD jets. Unlike HD jets, PFD jets develop current-driven instabilities that are exacerbated as cooling and rotation increase, resulting in jets that are clumpier than those in the HD limit. Our PFD jet simulations also resemble the magnetic towers that have been recently created in laboratory astrophysical jet experiments.
Blackman Eric G.
Chittenden Jeremy P.
Ciardi Andrea
Frank Adam
Hartigan Patrick M.
No associations
LandOfFree
Comparing Poynting flux dominated magnetic towers with kinetic-energy dominated jets does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Comparing Poynting flux dominated magnetic towers with kinetic-energy dominated jets, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Comparing Poynting flux dominated magnetic towers with kinetic-energy dominated jets will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-31049